NAME

SYNOPSIS

DESCRIPTION

While Postscript does not use the # as a comment delimiter, peps will not pass the first line of its input to Ghostscript, if that line starts with a #. This is to allow the Unix shell to treat encapsulated Postscript files as executable scripts.

Peps can be used on line to produce images on the fly using the standard CGI interface. Xpeps can be used to debug online peps scripts before posting them on line.

OPTIONS

In the description of the switches, unless xpeps is mentioned explicitly, any time peps is discussed, the discussion also applies to xpeps.

-a <angle>

Declare the angle of rotation of the image in degrees, about the center of the image. By default the angle is 0, that is no rotation. A positive angle rotates the image counter-clockwise, a negative one clockwise.

Rotation almost always results in a part of the image being cut off. This can be prevented by using the -x, -X, -y, and -Y switches, or by changing the bounding box with the -b switch.

-b <left> <bottom> <right> <top>

Override the bounding box, which, by default, is read from the EPS file header. When this switch is used, peps completely ignores the EPS file header. That means the input does not even need to have an EPS header.

-c

Print HTTP content type, i.e. the MIME type. Xpeps always ignores this option. Peps ignores it if you select an output file instead of the default stdout. The content type depends on the type of bitmap produced. Peps will print the HTTP content type followed by two new lines into stdout and only then will it instruct Ghostscript to produce the bitmap and to send it to stdout. This lets you use peps as a CGI program on web sites to produce on the fly images.

Additionally, if gzip compression is turned on, whether by default or with the -z switch, peps will also print the correct HTTP content encoding to stdout.

-C

Print HTTP content type and exit. Like with the -c option, peps will print the MIME type to stdout. Unlike that, however, it will follow the MIME type by only one new line, and then it will exit without processing any input. This is useful for CGI programming when you want full control of the HTTP header. If xpeps sees this switch, it just exits.

-d

Show defaults. Since system administrators can compile peps and xpeps with different defaults, you can use this switch to see what defaults are used on your system.

-e [time]

By default, xpeps waits for you to press enter before removing the image from the display. With this option, xpeps will run in the background and will wait for time seconds before removing the image. If you do not specify the time, xpeps will use the default time to wait. This is a very long time (68 years on 32-bit machines), though your system administrator may have compiled xpeps with a shorter default. You can find out the default time by running

xpeps -d

This option has no effect on peps.

-E [time]

Same as -e, but xpeps will also print its pid on stdout. This will allow you to kill xpeps when you no longer need to see the image. Please note that just closing the window showing the image will not automatically kill xpeps, you need to kill it explicitly, or wait till time seconds expire (which can be never if you do not specify time explicitly).

-f <format>

Output in a different bitmap format, where format is a Ghostscript bitmap/pixmap output device. This option has no effect on xpeps.

-g 1 | 2 | 4

Anti-aliasing level of graphics. 1 is no anti-aliasing, 2 is some anti-aliasing, 4 is full anti-aliasing (default is 4). See also -l and -t.

-h <resolution>

Horizontal resolution in ppi (default 100). Overrides -w and -W, as well as the horizontal resolution set by -r.

-h

Stop processing the command line, show help and exit. Unlike the option above, it takes no parameters, so peps can distinguish between you asking for help and you setting the horizontal resolution.

-i

Use stdin for input. This is the default in version 2.0. Before that, peps did not accept input from stdin at all. There was a reason for that: While EPS files must have an EPS header before they start the actual Postscript code, the EPS specification allows the creators of EPS files to defer the %%BoundingBox comment to the trailer. That presents no problem with files which peps can process and rewind. But it does present a problem when reading the input from stdin which cannot be rewound.

As of version 2.0, peps accepts its input from stdin but in that case it requires that either the %%BoundingBox comment be in the header, or that you use the -b switch and set the bounding box explicitly.

-l 1 | 2 | 4

Anti-aliasing level of both, graphics and text. 1 is no anti-aliasing, 2 is some anti-aliasing, 4 is full anti-aliasing (default is 4). It is a shortcut for -g and -t when you want to set the same anti-aliasing level for both.

-m

Peps will output in monochrome (grayscale) PNG format. Xpeps will use the x11gray4 Ghostscript device (unless compiled with a different default).

-M <file>

If the -c or the -C switch is used, peps will look into file in search of the proper MIME type for the output format before it looks anywhere else. See the MIME section below for more details. This option has no effect on xpeps.

-n

Output in pnm format. This was the default in version 1.0. This option has no effect on xpeps.

-o <file>

Output to a file named file. By default peps sends its output to stdout. You can also request stdout explicitly by entering an empty file name, i.e. peps -o "" or peps -o ''.

-p

Output in color PNG format with peps, or to the x11 device with xpeps. As of version 2.0, this is the default on most systems though the system administrator has the option of using the pnm format with peps as the default, so it is a good idea to use the -p switch explicitly.

-q <height>

The output will be height pixels high. This overrides the vertical resolution set by the -v or -r switches and discards any overrides of vertical resolution made by the -Q or -W switches. By default the height of the bitmap is determined mathematically from the vertical resolution and the height of the bounding box. With this switch the vertical resolution is calculated from the height in pixels and the height of the bounding box. This switch does not affect the width of the bitmap or the horizontal resolution set by the -h, -r, -w or -W switches, but it does replace any override of the horizontal resolution made by the -Q switch. In other words, -Q 500 -q 100 has the same effect as -Q 100.

-Q <height>

Does everything the -q switch does, but also affects the width of the bitmap by setting the horizontal resolution the same as the new vertical resolution. As a result, the bitmap will be height pixels high while keeping its height/width ratio as determined by the bounding box. This switch overrides the -h, -q, -r and -v switches, and discards any overrides made by the -w and -W switches.

-r <resolution>

Vertical and horizontal resolution in ppi (default 100). Overrides -h, -q, -Q, -v, -w and -W.

-s

Turns off Ghostscript safety. By default peps passes the -dSAFER switch to Ghostscript which disables unsafe Postscript commands. With the -s option, peps will not use that Ghostscript switch. In most cases the use of this option should be avoided.

-t 1 | 2 | 4

Antialiasing level of text. 1 is no anti-aliasing, 2 is some anti-aliasing, 4 is full anti-aliasing (default is 4). See also -g and -l.

-u <user>

Search user's home directory for peps.mime. See the MIME section for details. This option has no effect on xpeps.

-v <resolution>

Vertical resolution in ppi (default 100). Overrides -q and -Q, as well as the vertical resolution set by -r.

-v

Stop processing the command line, print peps version and exit. Unlike the option above, this one takes no parameters, so peps can distinguish between the setting of the vertical resolution and the request to print its version.

-w <width>

The output will be width pixels wide. This overrides the horizontal resolution set by the -h or -r switches and discards any overrides of horizontal resolution made by the -Q or -W switches. By default the width of the bitmap is determined mathematically from the horizontal resolution and the width of the bounding box. With this switch the horizontal resolution is calculated from the width in pixels and the width of the bounding box. This switch does not affect the height of the bitmap or the vertical resolution set by the -q, -Q, -r or -v switches, but it does replace any override of the vertical resolution made by the -W switch. In other words, -W 500 -w 100 is the same as -W 100.

-W <width>

Does everything the -w switch does, but also affects the height of the bitmap by setting the vertical resolution the same as the new horizontal resolution. As a result, the bitmap will be width pixels wide while keeping its height/width ratio as determined by the bounding box. This switch overrides the -h, -r, -v and -w switches, and discards any overrides made by the -q and -Q switches.

-x <offset>

Pad the left side of the image by offset points. If offset is negative, a section of the left side of the image is removed. The value is in Postscript points (default 0).

-X <offset>

Pad the right side of the image by offset points. If offset is negative, a section of the right side of the image is removed. The value is in Postscript points (default 0).

-y <offset>

Pad the bottom of the image by offset points. If offset is negative, a section of the bottom of the image is removed. The value is in Postscript points (default 0).

-Y <offset>

Pad the top of the image by offset points. If offset is negative, a section of the top of the image is removed. The value is in Postscript points (default 0).

Effectively, the -x, -X, -y, and -Y switches allow you to add a frame around the image (its color will depend on the underlying Postscript code), or to crop the image.

-z

Turn on gzip compression. By default on most systems it is on when the -c switch is used and the HTTP_ACCEPT_ENCODING environmental variable lists gzip, off otherwise. The system administrators can, however, compile peps with different defaults, so the -z switch lets you turn it on explicitly. Regardless of the switch, the gzip compression is turned off when an output file is selected with -o. Of course, you can use redirection if you want to create a compressed file:

peps -z -m image.eps > image.png.gz

By the way, setting the GZIP environmetal variable to -9 will improve the compression. See gzip(1) for more details. If you are using the Apache web server, you can set it in the .htaccess file:

SetEnv GZIP -9

This switch has no effect on xpeps.

-Z

Turn off gzip compression. This switch has no effect on xpeps.

file

Use file for input. By default, peps uses stdin for its input. You can override it by typing a file name on the command line, before or after any switches (of course, if a switch takes additional parameters, you need to type the file name after the parameters). Peps will treat the file name as it treats any other option, so if you enter more than one file name, peps will use the last one.

That also means that -i file works as expected: file will be the input. Though -i tells peps to use stdin, the file name that follows will override it, making file the input.

In the unlikely case that the name of the file starts with a -, precede it with another -, otherwise peps will think it is a switch. So, if the input file name is -weird-, enter it on the command line like this:

--weird-

See http://peps.redprince.net for further details and examples.

MIME

Peps will search the following places in the following order:

1.

The file specified with the -M switch.

2.

The file peps.mime located in a user directory. Which user? If the -u switch is used, in the home directory of the user specified by the switch. If the -u switch is not used, it will use the home directory of the user specified by the PEPSMIME environmental variable. If neither the -u switch is used nor does the PEPSMIME environmental variable exist, peps will look for peps.mime in the home directory of the effective user running peps.

3.

The file peps.mime located in a system directory. By default that directory is /etc, but the system administrator can compile peps to look for it in a different directory.

4.

A list hardcoded in peps.

If peps does not find the MIME in any of the above, it will default to image/x-device, where device is the Ghostscript device used.

Because web servers normally run as nobody or a similar special user, it is necessary to inform peps which user's home directory to search for peps.mime. This can be done explicitly with -u switch. But it is so easy to forget to use the switch or perhaps to make a typing mistake. It is, therefore, a good idea to tell the web server to set the PEPSMIME environmental variable. On the Apache server, this can be accomplished by entering the following in the .htaccess file:

SetEnv PEPSMIME user

Substitute the actual user name for user. Remember to keep peps.mime readable by the process running the web server. This can be accomplished by issuing the following command:

chmod 644 peps.mime

It is only necessary to issue this command once.

SEE ALSO

gs(1), gzip(1)

HISTORY